                     (filterv (complement nil?)))]
       (if (seq data)
         data
-        (log/error
+        (println-err
          (trs "Supplied directory {0} contains no usable data!" dir))))))
 
 (def producers (vec (repeatedly 4 #(random-string 10))))

          (if (> time-diff 5000)
            (let [time-diff-seconds (/ time-diff 1000)
                  messages-per-second (float (/ events-since-last-report time-diff-seconds))]
              (println "Sending" messages-per-second "messages/s"
                       "(load equivalent to" (int (/ messages-per-second expected-node-message-rate)) "nodes)")
              (flush)
              (recur 0 t))
            (recur (inc events-since-last-report) last-report-time)))))))


  (try
    (json/parse-string (slurp file))
    (catch Exception e
      (println-err (trs "Error parsing {0}; skipping" file)))))

(defn load-sample-data
  "Load all .json files contained in `dir`."
